The present disclosure generally relates to an arrangement for, and a method of, analyzing wireless local area network (WLAN) field coverage in a venue, either indoors or outdoors.
For product locationing, product tracking, product identification, and inventory control of products in a retail, factory, or warehouse environment, or a like indoor or outdoor venue, it is known to wirelessly link one or more mobile data capture devices in a wireless local area network (WLAN) having a plurality of base stations (e.g., access points) deployed in the venue under the control of a network computer or host server. For example, one type of mobile data capture device may be a radio frequency (RF) identification (RFID) tag reader for reading RFID tags, and/or a near field communication (NFC) tag reader for reading NFC tags, the tags being associated with the products in the venue, and another type of mobile data capture device may be either a laser-based or an imager-based bar code symbol reader for reading bar code symbols associated with the products in the venue. The base stations propagate a WLAN field in the venue by transmitting and receiving RF signals to and from such mobile devices to enable the users of the mobile devices to move freely within the venue and still be connected to the WLAN, and, if desired, to the wider Internet. Many modern WLANs are advantageously based on the Institute of Electrical and Electronics Engineers (IEEE) 802.11 standards, marketed under the Wireless Fidelity (Wi-Fi) brand name.
It is often important to analyze or map the coverage of the WLAN field of the RF signals propagated by the base stations in the venue, both prior to establishing the WLAN during network planning, and after establishing the WLAN during monitoring/debugging. Strong RF signal coverage is typically found in certain so-called “hot” zones in the venue, typically in the immediate vicinity of each base station. However, some RF signals may be reflected and/or scattered along multiple, folded paths, and/or at least partially absorbed, by walls, ceilings, floors, shelving structures, and like permanent fixtures and obstructions. In addition, some RF signals may, from time to time, be unpredictably and temporarily attenuated by people walking through the venue, or by forklifts driving through the venue, or by doors being closed, or by some transitory movement of another object or person. Such multi-path propagation and transitory environmental conditions may cause weak, poor, or even no WLAN field coverage in certain so-called “cold” zones in the venue and may compromise network communications and data capture performance. Additional base stations or other network hardware, or additional software, may need to be deployed and configured to provide more uniform and adequate WLAN field coverage in the venue, especially in the cold zones, thereby burdening customer support personnel and resources.
It is known to perform a site survey to analyze the WLAN field coverage in a venue by sampling the RF signals propagated by the base stations. Although generally satisfactory for its intended purpose, the survey or mapped data produced by such sampling is only valid for the time, and only for the specific physical obstructions and/or environmental conditions, during which the survey was conducted. A network analyst reviewing the survey data will not know, for example, whether a particular cold zone was caused by poor deployment of the base stations, or by the presence of some permanent fixture or obstruction, or by some temporary environmental condition such as the transitory movement of some object or person, among other factors. Once the survey is completed, the analyst may not readily be able to resurrect the physical obstructions and/or environmental conditions during which the survey was conducted. This may lead to an incorrect WLAN field coverage analysis. For example, a particular temporary obstruction and/or environmental condition may not recur, and a zone deemed cold at one time may actually be hot at another time.
Accordingly, it would be desirable to render the WLAN field coverage analysis more accurate for network planning/monitoring/debugging purposes, to reduce the burden on customer support personnel and resources, and to readily enable an analyst to resurrect the physical obstructions and/or environmental conditions in which a site survey was conducted.
Skilled artisans will appreciate that elements in the figures are illustrated for simplicity and clarity and have not necessarily been drawn to scale. For example, the dimensions and locations of some of the elements in the figures may be exaggerated relative to other elements to help to improve understanding of embodiments of the present invention.
The arrangement and method components have been represented where appropriate by conventional symbols in the drawings, showing only those specific details that are pertinent to understanding the embodiments of the present invention so as not to obscure the disclosure with details that will be readily apparent to those of ordinary skill in the art having the benefit of the description herein.